#!/usr/bin/env node
var pi = Math.PI;

module.exports = function(radius) {
    function circumference(){
        return pi * 2 * radius;
    }

    function area() {
        return pi * radius * radius;
    }

    return {
        area: area,
        circumference: circumference
    };
}

console.log('\n03-export-function:\n', module);